The development of lightweight, relatively inexpensive, battery-powered electronic transmitters and receivers has led to amusement systems which allow one or more participants to engage in simulated warfare. Each participant carries a "weapon" which can be triggered to send out a directional emission. Participants wear sensors which can detect a "hit" by an opponent.
U.S. Pat. No. 4,695,058 discloses an amusement shooting game of this type which is played in a structure including paths along which the participants move and obstacles which they must negotiate to locate and hide from their "enemy." A central computer includes sensors which monitor the operation of the game in terms of the locations of the players and their hits upon one another and generates scores which are displayed to the players and special effects such as sounds and explosions. Systems of this type can provide the players with the "virtual reality" of a battlefield.
Somewhat related amusement systems have been developed in which the weapons carried by the players can be used to fire "paint balls" at opponents. The paint balls consist of thin plastic capsules carrying a marking fluid, which break upon impact with an object or another player to mark a "hit." Electronic sensors can detect a hit and score a player's performance.
An independent development is on the rise in popularity of in-line roller skates or "roller blades." This has led to the development of arenas in which the skaters repetitively skate in circles.